A differential signal includes an associated common mode voltage. The common mode voltage is typically defined as the voltage midway between the voltage corresponding to a high logic state and the voltage corresponding to a low logic state of the differential signal. Due to various imperfections in analog signal processing circuits, the common mode voltage of a differential signal may vary. In some cases, the variation in the common mode voltage of a differential signal is large enough that it creates problems for a circuit configured to process the differential signal.
Accordingly, there is a need for controlling a common mode voltage of a differential signal to prevent operational errors in circuits configured to process the differential signal.